Yes, what you posted is exactly what I found when searching. So I was not missing anything as far as a requirements for adding a stopover? I am not very familiar with AS Mileage Plan.

I will call and thank you for running through it. Are there other examples with AS and other partner airlines not allowing stopovers like this? Seems like you may have been familiar with it. Just curious if you already knew of this issue through KEF on FI or other routes?